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arXiv · 2307.13023

Limits on dark matter annihilation in prompt cusps from the isotropic gamma-ray background

M. Sten Delos·Michael Korsmeier·Axel Widmark·Carlos Blanco·Tim Linden·Simon D. M. White
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Abstract

Recent studies indicate that thermally produced dark matter will form highly concentrated, low-mass cusps in the early universe that often survive until the present. While these cusps contain a small fraction of the dark matter, their high density significantly increases the expected gamma-ray flux from dark matter annihilation, particularly in searches of large angular regions. We utilize 14 years of Fermi-LAT data to set strong constraints on dark matter annihilation through a detailed study of the isotropic gamma-ray background, excluding with 95% confidence dark matter annihilation to $b\bar{b}$ final states for dark matter masses below 120 GeV.

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M. Sten Delos, Michael Korsmeier, Axel Widmark, Carlos Blanco, Tim Linden, Simon D. M. White. 2023-07-24. Limits on dark matter annihilation in prompt cusps from the isotropic gamma-ray background. https://doi.org/10.1103/physrevd.109.083512

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